Motional EMF (direction of moving bar)

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To determine the direction of the velocity of a conducting bar inducing a current, the magnetic force (Fb) and gravitational force (Fg) must be analyzed. The equation Fb=q(VxB) can be simplified to F=ILxB for clarity. In a steady state where Fb exceeds Fg, the motional emf does not equate to Fb-Fg directed to the right, as the magnetic force opposes the motion. The confusion arises from the relationship between the induced current and the magnetic force, which can sometimes appear counterintuitive. Understanding that the magnetic force always opposes the direction of motion is crucial for accurately determining the system's behavior.
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Homework Statement



Can someone please explain to me how to determine the direction of the veloicty of a bar that is conducting and inducing a current.

Fb=q(VxB)?
 
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Use F = IL x B instead.
 
Consider a conducting wire attached to a small weight. Fg acts to the right, and Fb (due to magnetic field perpendicular) is directed to the left. Say Fb>Fg. If the system is allowed to reach "steady state" why is the motional emf not Fb-Fg and directed to the right?
 
The only reason I am asking is that I read that the magnetic force that develops due to a velocity always has to oppose it... Which doesn't seem like it would always be the case. Especially if there is a current passing through the wire such that it is that force giving it the acceleration.
 
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